If you have access to any streaming data source, what would you create?

Helpline

I would like to have a helpline service.. A police car / a rescue vehicle / an mobile emergency team should have their data streaming on an app which gives their current location with contact number. A person in an emergency or anyone in distress situation (accident for example) can contact these close vicinity help vehicles directly instead of having to go through a central helpline. Maybe a distress button on the app or a patterned tap of the mobile keys send out a distress signal with exact location of the person in trouble to the closest help nearby.